1. Field of the Invention
The present invention relates to a vehicle brake hydraulic pressure control unit which is characterized in a mounting construction of assembled parts such as an electromagnetic valve, a pump and a pressure sensor.
2. Description of Related Art
As vehicle brake hydraulic pressure control units for controlling the magnitude of a brake hydraulic pressure which is applied to wheel brakes, there are known vehicle brake hydraulic pressure control units which include a base body which incorporates therein a brake fluid flow path and assembled parts such as an electromagnetic valve, a pump and a pressure sensor (for example, refer to Japanese Patent Unexamined Publication No. JP-A-2001-280533).
Incidentally, in JP-A-2001-280533, an electromagnetic valve, which is one of assembled parts, is assembled in place in a bottomed mounting hole portion which is provided in a base body in such a manner as to communicate with a flow path in an interior of the base body by depressing a relevant location of the surface of the base body thereinto. In addition, in JP-A-2001-280533, a plastically deformed portion is formed on a hole wall of the mounting hole portion by inserting a lower end portion of the electromagnetic valve into a lower portion of the mounting hole portion for clamping and thereafter pressing the surface of the base body around the periphery of an opening in the mounting hole portion, and the plastically deformed portion so formed is caused to enter a locking groove formed on an outer circumferential surface of the electromagnetic valve, so as to prevent the dislocation of the electromagnetic valve from the mounting hole portion.
Incidentally, when the lower end portion of the electromagnetic valve is press fitted in the lower portion of the mounting hole portion, the lower end portion of the electromagnetic valve needs to be caused to slide along the hole wall of the mounting hole portion. Therefore, there may occur a case where fine chippings (metallic ones) are produced in the lower portion of the mounting hole portion, depending upon a combination of tolerances in the dimensions of the relevant parts.
In the event that the chippings so produced are mixed into brake fluid, there is caused a fear that the sliding resistance is increased in the slide portion of the vehicle brake hydraulic pressure control unit, and to be worse, there is caused a fear that the seal portion is worn.
In addition, the aforesaid problem applies to the electromagnetic valve which constitutes the assembled part, in addition, the aforesaid problem applies to the pump, the reservoir and the pressure sensor when they constitute the assembled part.